Sand-blasting machine



March 10, 1925.

L. v. MATHER SAND BLAS TING MACHINE iled July 23, 1921 5 Sheets-Sheet 1 March 10. 1925.

L. V. MATHER.

SAND BLASTING MACHINE 5 Sheets-Sheet 2 Filed July 1921 I M r .T H u J 2 =22: g E Z i l g m w H W EH. a mm H March 10, 1925.

L. V. MATHER SAND BLASTING MACHINE Filed July 23, 1921 r 5 Sheets-Sheet 5 abto'mmro March 1-0. 1925 1,528,885 8 L. V. MATHER SAND BLASTING MACHINE Filed July 23, 1921 5 Sheets-Sheet 4 F n u u u u Elli El i

March 10, 1925. 1,528,885-

L. v. MATHER SAND BLASTING MACHINE Filed July 5, 1921 5 Sheets-Sheet 5 3mm 6025 1 /'Z a 6/1 er Patented Mar. 10, 1925.

1,528,885 PATENT OFFICE.

UNITEDv STATES LEWIS V. MATHEB, OF DETROIT, MICHIGAN.

SAND-BLASTING MACHINE.

Application filed July 23, 1921. Serial- N'o. 487,208.

electro-plating of articles, and it is the ob-' ject of the invention to thoroughly clean the articles before introduction into the electrolytic bath.

In the present state of the art it is usual to clean the surface of articles which are to be electro-plated, by subjecting the same to a pickling process. This is objectionable for various reasons, one of which is the fact that the pickling process requires a considerable time interval for its accomplishment. The present invention greatly simplifies and expedites the cleaning by substituting for the pickling process a sand-blasting process, and the construction is so devised that every portion of the surface which is to be plated is thoroughly cleaned from scale or other matter which would interfere with the elec trolytic deposit. My improved apparatus, therefore, comprises essentially a sand-blasting machine, but it is associated with other devices, which will facilitate the thorough cleaning and the removal'of all dust from the cleaned surface. To this end the invention consists in the construction as herein- 7 after set forth.

In the drawings:

Figure 1 is a diagrammatic sectional elevation of the machine;

Figure 2 is a plan view of a portion thereof;

Figure 3 is a side elevation of the sandblasting apparatus;

Figure 4 is an. end elevation thereof;

Fi re 5 is an elevation of the intermittently operating mechanism;

Figure 6 is an enlarged view of a portion of Fig. 4:;

Figures and 8 are diagrams showing the arrangement of sand-blasting nozzles.

With my improved apparatus it would be possible to eflfect the cleaning solely by the sand-blasting operation, but this cleaning is facilitated and expedited by first removing from the surface of the article the grease roll when propelled by the chain.

with which it is coated in the machining operations. After the sand-blasting there will still be adhering to the surface a fine coating of dust, and to insure the complete removal of this coating I have provided means for washing the articles in advance of their introduction to the electrolytic bath. Therefore, my improved apparatus comprises; first, an alkaline bath; second, the sandblasting machine; and third, a washing apparatus.

It is one object of the invention to render the apparatus entirely automatic and to this endl have provided a positively actuated conveyor which carries the work first through the alkaline bath, then the sand-blasting apparatus and then the washing apparatus, finally delivering the articles to an electrolytic bath. As specifically shown, the ap* paratus is designed for the cleaning of wheel rims, the detail construction being as follows:

A is a frame in which is mounted a series of parallelly arranged conveyors B. Each of the conveyors consists of a pair of link chains B and B having rollers C extending therebetween at the pivots thereof and supporting wheels or rollers D outside of the chains which run in channel tracks or guide. ways E. The chains pass around sprocket wheels F at opposite ends of the frame and the return portion of the chain is arranged at the top of the frame out of the way of the operating apparatus. The spacing between the rolls G is such as to receive with some clearance the work to be conveyed, which in this instance is a wheel rim. The width of the rim is slightly less than the distance between the parallel chain links and beneath the chain and parallel to the guideways E are tracks G over which the rims Thus all of the parallel conveyors B will operate simultaneously to convey parallel series of rims through the frame and over the tracks G.

At the entrance end of the frame is arranged thealkaline bath. This comprises a tank H containing a hot alkaline solution and in registration with this tank the tracks G and E are dipped so as to immerse a portion of the rims beneath the surface of the liquid, while passing .over the tank. The

of rest the rims are brought in contact with revolving rolls I. These will slowly rotate the rims in contact therewith so that all portions of the surface will be passed he'- neath the surface of the liquid to insure complete removal of the grease. Also, as the liquid is boiling hot, sufficient heat will be imparted to the rims to effect a quick drying when removed from the solution.

In the central portion of the frame A is arranged the sand-blasting apparatus, which comprises an enclosed chamber J, preferably of suflicient dimensions to include two of the station points of the rim conveyors in the intermittent movement thereof. At each of these station points the rims are brought into contact with revolving rollers K mounted on rotating shafts K driven at a speed to slowly revolve the rims for at least one complete revolution. Above the chamber J there are arranged sand hoppers L from which sand is delivered to a series of blast nozzles directed against zones in the surface of the rim. As shown in Figure 3, which illustrates the work as a clincher type rim, there are eight blast nozzles in connection with the rims, a part of which are directed against the inner surface and another part against the outer surface. These nozzles are so arranged that each covers a segment of a zone extending transversely of the rim and are supplemental to each other so that by rotating the rim while exposed to each of the nozzles the entire surface of the rim will be exposed to the blasting action. The blasting action is intermittent, only occurring during the intervals of rest of the conveyors and the apparatus is therefore provided with timed mechanism for starting and stopping the feeding of sand and air to correspond with these intervals of rest, the specific mechanism being as follows:

L are sand cut-ofi's arranged beneath each of the hoppers L and consisting of troughs sufficiently near to the discharge slot from the hopper to choke the flow of the stream.

The troughs L are supported upon rock arms L by which they may be moved out of registration with the discharge slit from the hopper, permitting the discharged sand to enter a trough L having a series of nipples L. Each nipple is connected by a hose or flexible conduit with one of the sand blast nozzles M, the number of nipples being sufficient for all of the nozzles required for the parallel series of rims. The air for blasting is supplied from a tank N from which it is conveyed through a. conduit N controlled by a valve N to headers or manifolds N connected by flexible conduits N to the nozzles. The valve N is operated simultaneously with the operation of the rock arms L which control the sand cut-0E and the timing is such that both the air and is removed.

the sand are cut ofi when the conveyors are in movement and are started simultaneously when the conveyors are at rest.

To permit of the entrance and exit of the rims, the chamber J is provided with doors and these are preferably self-closing and are opened by the work when passing in or out of the chamber. As shown, 0 and O are doors above the chain and O and O are doors below the chain. These, together with one of the rolls C, which stops in registration with said doors, will form a complete closure when the chain is at rest. When, however, the chain is in motion,the rims which are propelled thereby will automatically open the doors both in entering and leaving the chamber.

At the end of the frame from which the rims are discharged is arranged a washing device by which the dust coating covering the sand blasted surface This washing device includes a tank P above which are arranged rolls Q, Q, Q and Q similar to the rollers K, in the sand-blasting device and supporting the rims when the chain is at rest. The rolls are driven so as to impart to the rims a slow rotational movement and water jets R are directed against a zone of the rim so that after a complete revolution the whole of the surface is thoroughly cleansed. The jets operating upon the rim at one station point may be hot water jets and those at the other station point cold water jets, this being more effective than treatment with either hot or cold water alone;

From the end of the frame A the rims are discharged onto an inclined platform from which they roll into engagement with the automatic feed for carrying the same through the electrolytic bath. As this part of the apparatus forms no portion of the present invention, it is merely indicated in the drawings in dotted lines.

The driving and timing of the machine is effected by any suitable construction of mechanism, but as shown, S is a motor from which is driven achain S carrying a. driving dog S for engagement with the notches S of the wheel 8*, which latter drives the sprocket wheels F. The dog' S automatically engages with one of the notches S and after moving the wheel S through an 4 angle equal to that between adjacent notches, a trip S will cause disengagement. Thus the interval in which the wheel S is driven is only that portion of the complete I cycle corresponding to the ratio between the distance between notches of the wheel and the full length of the chain. Therefore,-the work carriers are at rest for the great part of the time and are only in motion during a small portion of the cycle.

The other parts of the mechanism are operated by suitable'drive connections including the chains T, T and T through which the rollers K, and Q, Q, etc., are driven. The sand cut-off L and the air valve N are actuated by a link U connected to a crank U, which is intermittently rotated by a sprocket U engaging certain links V of the chain T. The chain T is in a position where the links thereof normally clear the sprocket U but the links V are provided with roller bearings V for engaging a cam V which presses said links into engagement with the sprocket. This will impart to the sprocket one complete revolution before the chain again disengages therefrom and this revolution will through the crank U reciprocate the link U operating the rock arms L and sand cut-off L. Also, the link U will actuate the valve N whereby the sandblast will be in operation for all of the cycle, with the exception of the interval in which the link U is reciprocating.

In the complete 0 ration of the machine the wheel rims are rst placed iipon an inclined platform W from which they will roll into engagement with the conveyors B when in registration therewith. The rims are then advanced by said conveyor step by step until they are finally discharged at the opposite end of the frame into the electrolytic tank. As has been described, the rims are rotated while dipped into the tank H to effect a removal of'the grease by the alkaline solution. They are again rotated within the chamber J where the sand-blasting is effected and are finally rotated in the washing apparatus, where the dust is removed from the surface.

\Vhat I claim as my invention is:

1. The combination with a plurality of parallel runways for a series of wheel rims, a housing into which the rims in said runways are periodically introduced, means within said housing for simultaneously rotating all of the rims within said housing, sand-blast nozzles each arranged to cover a zone segmenton the surface of each rim, which is progressively advanced during the rotation of said rims, and means operating after each cycle for removing the cleaned rims and introducing from said runways rims to be cleaned.

2. The combination with a housing, of means for periodically introducing into and removing from said housing a series of axially coincident parallelly arranged wheel rims, means for simultaneously rotating all of the rims in said series, sand-blasting means for impinging against a zone segment of the surface of each rim, which is progressively advanced during the rotation thereof, said rotating means and means for introducing and removing the rims being timed in relation to each other.

3. The combination with a housing, of a driven roll in said housing, means for periodically introducing into said housing a series of axially coincident parallelly arranged wheel rims resting upon said driven roll and frictionally rotated thereby, and sand-blasting means for impinging against a zone of the surface of each rim, which is progressively advanced during the rotation thereof.

4. The combination with a housing, means for periodically introducing and removing from said housing wheel rims, means for rotating said rims about their axes while in said housing, and a plurality of sand blast jets arranged to be directed against the surfaces of the rims, said jets being supplemental to each other, each covering a. zone segment, which segments together completely encircle. the cross sec tional contour of the rims.

5. The combination with a housing, of means for periodically introdncing a rim into said housing, a plurality of sand blast jets directed against the surface of said rim,

said jets being supplemental to each? other,

each covering a segment of a zone, which segments together completely encircle the cross sectional contour of the rim, means for rotating said rim while exposed to the action of said jets, and means for removing said rim from said housing upon the completion of the rotation.

In testimony whereof I affix my signa ture.

LEWIS V. MATHER 

